SD Padhacking: Dreamcast Edition (Worklog)


#1

First off, the SD is for “Super Deformed.” I thought it was an apt classification for such pad hacks.

I have an obsession with taking apart my gaming hardware and trying to make it smaller :bgrin: As usual, I’m in the middle of like 8 projects, but I thought I’d post some pics/thoughts on the progress I’ve made on this one so far.

Here’s basically the smallest square you can get out of the Sega HKT-7700 without having to rebuild stuff:

The reason I moved the three electrolytic capacitors was because I wanted to achieve the lowest profile possible (they stick up pretty high and keep it from fitting into the housing I want to put it in).

Here’s a shot of the bottom (rosin core solder makes it look nasty) after tinning most of the solder points for both game control and VMU support:

Those surface mount resistors were cannibalized from portions of the PCB which were removed. The big 0 ohm resistor just connects a floating ground plane, while the two smaller resistors were used to make a voltage reference for the analog stick signals. The extra red wire just goes to ground so I can test all the digital inputs.

Here’s a shot of the SD PCB soldered directly to a VMU:

All digital inputs are still functional. In removing the op-amp section for each analog trigger, we lose the inversion of those signals, so a trigger inversion mod must be added. I tested a PNP transistor mod on the right trigger yesterday, but for optimal placement of parts, I think I’m going to switch over to an NPN setup for both analog triggers.

I’ll probably post some more detailed guide pics later w/ all the solder points and such when I feel I’ve arrived at the best part/wire placement :tup:
-ud


#2

I like doing that to stuff.

Is the PCB going to be inside VMU?


#3

Well, that’s one project :bgrin: I was going to cram one inside a VMU like a project box for a universal stick and another to go inside an original GameBoy cartridge :karate:
-ud


#4

Haha, sweet. I like cutting up PCBs to get them small too. One of my favorite things about the old Saturn PCBs was how small they were stock, just by clipping off the ‘wings’.


#5

Going along these lines would be great for my mega-retro project box project.


#6

Don’t worry, there will be more to come :bgrin: I intend on doing tutorials for most 1st party controllers (I’m almost done w/ GC & DC) and a few other 3rd parties (Madcats XBOX 360 retro stick, for example). From the sound of it, you might want to check this action out, if you haven’t already.
-ud


#7

I’ve glanced at that thread. My end goal is for one big box that has padhacks setup to project box Neo/3DO/TG16/Jaguar/CD-i/CD32/PC-FX to be used with an SNES pad. One cable in the front for the pad and all the other cables coming out the back and into their respective systems. Gonna need to put in some sort of switch so that I can select what system it is going on at that time. Don’t care if it’s ugly, it’ll be in an entertainment system with a bunch of consoles that are nearly 20 years old but I would like to make it as small as possible (knowing it’ll be large no matter what).